I don't think the team would gain an extra win in overall value by playing Ohtani at first base vs more experienced options like Vlad, Biggio, Hortwitz etc. He would be facing a steep learning curve as it's doubtful he's played the position as a professional and would be facing an uphill battle to even become an average defender there in such a short time span. Of course Vlad was positively awful in 2023, but I suspect he will most likely be quite a bit better there in 2024.